Specific Valve stem seal install question

[WarWagon]

Where does the square "o-ring" go on the valve stem when being installed? In a groove just under the keeper grooves? Or does it go as far down on the stem as you can get it against the head?

I am removing the (shot) positive valve stem seals on the exhaust valves and going to just o-ring for all 16 valves. Rather the guides have a little more oil to work with on this engine unless this theory of mine is bad and I should use positive control seals on the exhaust.

 

[NVW]

IIRC just under the keeper.

 

[Twisted Steel Performance]

Slide it down the stem and when the valve moves it will move up the stem as needed the first time they move... I would use the cap seals where they were as stock for longer life...

 

[handcannon]

NVW is correct according to what a guy at a local auto machine shop told me. The end of the valve stem has two rings cut into it. The valve needs to be in place, with the spring and compressor in place. Then the O-ring is put into place just before the keeper is installed. It appears to me that when the spring compressor pressure is released the O-ring is pushed into the gap between the keeper and the formed "washer" that makes up part of the cap for the spring.

I was concerned about the washer hanging up on the first of the two grooves on the stem. So, I ended up finding a deep twelve point socket small enough that it was just barely larger than the diameter of the stem. I put the O-ring on the end of the stem, then used the socket to push the O-ring down past the first groove in the stem, and into the second groove. A piece of copper tubing, or other small pipe, could also probably be used to do the same thing.

Don